1. Field of the Invention
The present invention relates to an electromagnetic switch of a starter which is turned on in response to a magnetic attraction force generated in an electromagnet to start an operation of an engine.
2. Description of Related Art
A technique for automating assembly of an electromagnetic switch used for a starter has been proposed. in Published Japanese Patent First Publication No. 2002-313205. FIG. 1 is a sectional view showing attachment of a terminal to a conducting plate in an electromagnetic switch disclosed in this Publication.
As shown in FIG. 1, in an electromagnetic switch, a plate-shaped terminal 100 electrically connected with an electromagnetic coil (not shown) is protruded from a contact cover 110. The terminal 100 is joined to a conducting plate 120 on the outside of the cover 110 with solder. The plate 120 is connected with a terminal 130 of a motor (not shown). The motor is earthed. The terminal 130 is covered with the cover 110. When an ignition key (not shown) is turned on, an electric current set at a small value is supplied from a battery (not shown) to the coil and is transmitted to the earthed motor through the terminal 100, the plate 120 and the terminal 130. Therefore, the coil generates a magnetic field in response to the current, and an electric contact section (not shown) is turned on in response to the magnetic field. That is, the switch is turned on. Then, an electric current set at a large value is supplied from the battery to the motor through the electric contact section. Therefore, the motor generates a rotational force, and an operation of an engine of a vehicle (not shown) is started in response to the rotational force.
The cover 110 is disposed so as to protect contact members (not shown) of the switch. The terminal 100 has a stiffness larger than that of a terminal of the coil so as to maintain the shape of the terminal 100 on the outside of the cover 110. With this structure, because the terminal 100 having the stiffness is used to electrically connect the coil with the motor terminal 130, it is not required to extend a terminal of the coil to the outside of the cover 110. Therefore, assembly of an electromagnetic switch including the coil and the cover 110 can be automated.
In cases where the contact members of the switch are changed to new ones to perform maintenance of the switch, portions of the terminal 100 and the plate 120 joined together are cut off, and the cover 110 is taken off from the switch to expose the contact members to the outside of the switch. After the contact members are changed to new ones, the cover 110 is again attached to the switch, and it is tried to again join the terminal 100 and the plate 120 together on the outside of the cover 110.
However, because the joined portions of the terminal 100 and the plate 110 have been already removed, it is difficult to join the terminal 100 and the plate 120 together again on the outside of the cover 110. To join the terminal 100 and the plate 120 together in the maintenance of the switch, it is required to change the terminal 100 and the plate 120 to new ones. Therefore, cost required in the maintenance of the switch is heightened. Further, the coil is wound on a bobbin (not shown), and the terminal 100 is forcibly inserted into the bobbin to be fixed to the bobbin. Therefore, it is difficult to separate the terminal 100 from the bobbin, so that it is required to change both the terminal 100 and bobbin to new ones. Further, the number of work steps required to change parts of the switch is increased. Therefore, not only cost of changed parts is heightened, but also cost for the maintenance work is heightened.